Mexico City officials cancelled classes for millions of students yesterday for a second straight day as smoke from brush fires continued to choke the city of 9 million.
Both lower schools and universities were closed for the pollution alert and Mayor Claudia Sheinbaum said they would remain closed until today.
"We don't expect this situation to change until the weekend," Sheinbaum said.
She said a light, localised rain overnight had done little to cut the pollution. The Government reported that levels of particulate matter of 2.5 micrometres or less, known as PM2.5, had reached 148 micrograms per cubic metre of air. That's about six times the World Health Organisation's daily limit. Ozone levels were also high.
The city also declared a partial driving ban, but activists of the Citizen Observatory on Air Quality called for officials to limit polluting activities such as truck transportation and construction sites.